/*
 * Central Repository
 *
 * Copyright 2015-2020 Basis Technology Corp.
 * Contact: carrier <at> sleuthkit <dot> org
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.sleuthkit.autopsy.centralrepository.datamodel;

import java.util.Objects;
import java.util.regex.Pattern;

/**
 *
 * This class is a POJO for postgres settings to be used with central repository.
 */
public class PostgresConnectionSettings {
    private final static String DB_NAMES_REGEX = "[a-z][a-z0-9_]*"; // only lower case
    private final static String DB_USER_NAMES_REGEX = "[a-zA-Z]\\w*";
    
    public final static String DEFAULT_HOST = ""; // NON-NLS
    public final static int DEFAULT_PORT = 5432;
    public final static String DEFAULT_DBNAME = "central_repository"; // NON-NLS
    public final static String DEFAULT_USERNAME = "";
    public final static String DEFAULT_PASSWORD = "";
    
    private static void validateStr(String s, String errMessage) throws CentralRepoException {
        if (null == s || s.isEmpty())
            throw new CentralRepoException(errMessage);
    }
    
    private static void validateRegex(String s, String pattern, String errMessage) throws CentralRepoException {
        if (!Pattern.matches(pattern, s))
            throw new CentralRepoException(errMessage);
    }
    
    private static void validateNum(int num, Integer min, Integer max, String errMessage) throws CentralRepoException {
        if ((min != null && num < min) || (max != null && num > max))
            throw new CentralRepoException(errMessage);
    }
    
    private String host = DEFAULT_HOST;
    private int port = DEFAULT_PORT;
    private String dbName = DEFAULT_DBNAME;
    private int bulkThreshold = RdbmsCentralRepo.DEFAULT_BULK_THRESHHOLD;
    private String userName = DEFAULT_USERNAME;
    private String password = DEFAULT_PASSWORD;

    /**
     * This method retrieves the postgres host.
     * @return  The host for these settings.
     */
    public String getHost() {
        return host;
    }

    /**
     * This method returns the port number for these settings.
     * @return  The port number for these settings.
     */
    public int getPort() {
        return port;
    }

    /**
     * This method returns the database name for these settings.
     * @return  The database name for these settings.
     */
    public String getDbName() {
        return dbName;
    }

    /**
     * This method returns the bulk threshold.
     * @return      The bulk threshold.
     */
    public int getBulkThreshold() {
        return bulkThreshold;
    }

    /**
     * This method returns the username to use for this connection.
     * @return      The username to use.
     */
    public String getUserName() {
        return userName;
    }

    /**
     * This method returns the password to use for this connection.
     * @return      The password to use for this connection.
     */
    public String getPassword() {
        return password;
    }
    
 
    /**
     * This method sets the host for this connection.
     * NOTE: must be non-empty string.
     * @param host the host to set
     */
    public void setHost(String host) throws CentralRepoException {
        validateStr(host, "Invalid host name. Cannot be empty.");
        this.host = host;
    }


    /**
     * This method sets the port for this connection.
     * @param port  The port to set (must be [1,65535]).
     */
    public void setPort(int port) throws CentralRepoException {
        validateNum(port, 1, 65535, "Invalid port. Must be a number greater than 0.");
        this.port = port;
    }


    /**
     * This methods sets the name of the database.
     * NOTE: this name needs to be a valid postgres database name.
     * @param dbName The database name.
     */
    public void setDbName(String dbName) throws CentralRepoException {
        validateStr(dbName, "Invalid database name. Cannot be empty."); // NON-NLS
        validateRegex(dbName, DB_NAMES_REGEX, 
            "Invalid database name. Name must start with a lowercase letter and can only contain lowercase letters, numbers, and '_'."); // NON-NLS

        this.dbName = dbName.toLowerCase();
    }

    
    /**
     * This method sets the bulk threshold of this connection.
     * @param bulkThreshold     The bulk threshold to set (must be greater than 0).
     */
    public void setBulkThreshold(int bulkThreshold) throws CentralRepoException {
        validateNum(bulkThreshold, 1, null, "Invalid bulk threshold.");
        this.bulkThreshold = bulkThreshold;
    }

    
    /**
     * This method sets the username for this connection.
     * NOTE: must be a valid postgres username.
     * @param userName  The user name to set.
     */
    public void setUserName(String userName) throws CentralRepoException {
        validateStr(userName, "Invalid user name. Cannot be empty."); // NON-NLS
        validateRegex(userName, DB_USER_NAMES_REGEX, 
            "Invalid user name. Name must start with a letter and can only contain letters, numbers, and '_'.");
        
        this.userName = userName;
    }

    
    /**
     * This method sets the password for this connection.
     * @param password  The password to set.
     */
    public void setPassword(String password) throws CentralRepoException {
        validateStr(password, "Invalid user password. Cannot be empty.");
        this.password = password;
    }

    @Override
    public int hashCode() {
        int hash = 7;
        hash = 43 * hash + Objects.hashCode(this.host);
        hash = 43 * hash + this.port;
        hash = 43 * hash + Objects.hashCode(this.dbName);
        hash = 43 * hash + this.bulkThreshold;
        hash = 43 * hash + Objects.hashCode(this.userName);
        hash = 43 * hash + Objects.hashCode(this.password);
        return hash;
    }
    

    @Override
    public boolean equals(Object obj) {
        if (this == obj) {
            return true;
        }
        if (obj == null) {
            return false;
        }
        if (getClass() != obj.getClass()) {
            return false;
        }
        final PostgresConnectionSettings other = (PostgresConnectionSettings) obj;
        if (this.port != other.port) {
            return false;
        }
        if (this.bulkThreshold != other.bulkThreshold) {
            return false;
        }
        if (!Objects.equals(this.host, other.host)) {
            return false;
        }
        if (!Objects.equals(this.dbName, other.dbName)) {
            return false;
        }
        if (!Objects.equals(this.userName, other.userName)) {
            return false;
        }
        if (!Objects.equals(this.password, other.password)) {
            return false;
        }
        return true;
    }
}